Pie and Histogram

Pie Charts and Histograms are commonly used visualizations in Data Analytics.
They help represent proportions and data distributions clearly.

First, import Matplotlib:

import matplotlib.pyplot as plt

1. Pie Chart

A Pie Chart shows the proportion or percentage of categories in a dataset.

Example: Market Share

companies = ["Company A", "Company B", "Company C", "Company D"]
market_share = [40, 25, 20, 15]plt.pie(market_share, labels=companies)
plt.title("Market Share Distribution")
plt.show()

Adding Percentage Labels

plt.pie(market_share, labels=companies, autopct="%1.1f%%")
plt.title("Market Share Distribution")
plt.show()

Exploding a Slice

explode = [0.1, 0, 0, 0]plt.pie(market_share, labels=companies, autopct="%1.1f%%", explode=explode)
plt.title("Market Share Distribution")
plt.show()

When to Use Pie Chart:

  • Showing percentage distribution
  • Comparing parts of a whole
  • Presenting simple categorical breakdown

2. Histogram

A Histogram shows the distribution of numerical data.

It groups values into intervals (bins).

Example: Exam Scores Distribution

scores = [55, 60, 65, 70, 75, 80, 85, 90, 95, 60, 70, 80, 85]plt.hist(scores, bins=5)
plt.title("Exam Score Distribution")
plt.xlabel("Scores")
plt.ylabel("Frequency")
plt.show()

Adjusting Number of Bins

plt.hist(scores, bins=10)
plt.title("Exam Score Distribution")
plt.show()

When to Use Histogram:

  • Understanding data distribution
  • Detecting skewness
  • Identifying outliers
  • Analyzing frequency patterns

Pie Chart vs Histogram

Pie Chart:

  • Used for categorical data
  • Shows proportions
  • Represents parts of a whole

Histogram:

  • Used for numerical data
  • Shows frequency distribution
  • Represents data spread

Key Takeaway

Pie Charts help visualize proportions of categories, while Histograms help analyze the distribution of numerical data. Both are essential tools for understanding datasets in data analytics.

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